Tri-substituted isocyanurate



United States Patent Oflice 3,409,618 Patented Nov. 5, 1968 ABSTRACT OF THE DISCLOSURE Tri-substituted isocyanurates are prepared by rearrangement of aziridinyl formates or by reacting phenyl haloformates with aziridine. Said tri-substituted isocyanurates are bactericidal.

wherein Y is an electronegative group, n is an integer of -5, and A is oxygen or sulfur. The electronegative groups can be, e.g., chloro, nitro, bromo, trifiuoromethyl, and the like.

The compounds hereof are bactericidal, having partricular elfectiveness against Escherichia coli, as well as being pesticidal (US. Patent No. 3,075,979). They are also useful as intermediates in preparation of the known 4-(2-phenoxyethyl) urazoles by conventional methods.

Rearrangement of the starting aziridinyl formate I to the desired isocyanurate II proceeds at moderately elevated temperatures in a non-reactive, non-aqueous, nonalcoholic solvent, preferably one having a low dielectric constant, such as xylne, carbon tetrachloride and the like. Normally the reaction to good yields is slow, particularly at room temperatures and below. Raising the temperature short of the boiling point of the resulting solution speeds the reaction, as does the presence of tertiary amines (e.g., pyridine, dimethylaniline, triethylamine, tributylamine, triethanolamine, triethylenediamine, and the like), a thiosulfate, or non-reactive substances giving a phenoxy or halide ion as catalysts. Reaction pressures are not critical, atmospheric conditions being preferred for convenience.

Alternatively, the isocyanurate II can be obtained by reacting an appropriately-Snbstituted phenyl haloformate with ethyleneimine according to the following reaction scheme:

tertiary HN H amine II III IV wherein Y, A and n have the values above assigned, and X is chloro, bromo or iodo. The reaction is conducted in the presence of a tertiary amine, such as pyridine, dimethylaniline, triethylamine, tribu tylamine, 'triethanolamine, triethylenediamine, and the like.

The concentration of tertiary amine in the reaction mixture governs the direction of the reaction. Thus, greater than about a 1:1 molar ratio of tertiary amine to phenyl haloformate gives the desired isocyanurate II, while less than about a 1:1 molar ratio favors production of the aziridinyl formate I.

In this alternative procedure solvents for the reactants are not necessary. However, where solvents are employed they desirably are those of non-polar character, such as the aromatic, aliphatic, or cycloaliphatic liquid hydrocarbons, including, e.g., benzene, toluene, heptane, xylene and the like.

The reaction III-l-IV proceeds satisfactorily over a relatively broad temperature range, the upper limit being marked by the boiling point of any solvent employed. However, temperatures of 0-50 C. are preferred. Pressures are not critical, atmosphreic pressure being commen as a matter of convenience.

In both reactions for direct production of the isocyanurate II, separation of the product is by conventional means, as typified hereinafter.

The following examples illustrate the invention as described, but in no sense are they to be construed as limiting the scope thereof.

Example l.-Tris 2-(2,4-dichl orophenoxy) ethyl] isocyanurate Into a reaction vessel equipped with means for stirring, temperature control and refluxing was charged a 20% (by weight) solution of 2,4-dichlorophenyl aziridiny formate in xylene (5- gm. in 20 gm. of xylene). To this was added 0.1 gm. of sodium-2,4 dichlorophenoxide. The reaction mixture was heated for 70.5 hours at 142 C. At the end of this time the solvent was removed under reduced pressure. Recrystallization from cyclohexaneacetone (2:1) gave 64% yield-sot essentially pure tris[2- (2,4- dichlorophenoxy)ethyl]isocyanurate, M.P. 15l- 152 C. IR analysis was consistent with the structure.

Example 2.Tris[2-(2,4-dichlorophenoxy)ethyl] isocyanurate Following the procedure of Example 1 but employing a 20% solution of 2,4-dichlorophenyl aziridinyl formate in carbon tetrachloride (3.2 gm. in 12.8 gm. of carbon tetrachloride), the reaction mixture was heated for 8 hours and 50 minutes at C. in the presence of 0.1 gram of triethylamine catalyst. The solvent was removed under reduced pressure. IR analysis showed the reaction mixture to contain 69% yield of tris[2-(2,4-dichlorophenoxy)ethylJisocyanurate. This product was recrystallized from a cyclohexane-acetone (1:1) to give a recrystallized product melting at 152 C.

Example 3.Tris [2-(4-nitrophenoxy)ethyljisocyanurate Following the procedure of Example 2 but substituting 4-nitrophenyl aziridinyl formate for the 2,4-dichlorophenyl aziridinyl formate therein and heating the reaction mixture for 20 hours at 56 C. gave tris[2-(4-nitrophenoxy)ethyl]isocyanurate.

isocyarriurate mixture was 'stirredHat. room. temperature for about 20 minutesand filtered freeof triethylamine hydrochloride. Thefilter cakewas: washed with .50, ml. ofdiethylketone and the filtrates combined. Evaporation of solvent gave 14.90 gm...(- 70% oith retical) f white, glittering plates having a. crude M'.P. of 61-63 C. analyses were -.;c onsisten t witl 1 the structure for p-chlorophenyl aziridinyl thiotormate. Allowing thisuproduct to stand at room temperature in a stoppered bottlefor 1.25 hours caused the solid to melt into 'a colorless oilvOn standingfurther at-roomtemperature resolidified into a-white solid mass;Recrystallization from acetone-methanol mixture gave a white powder,,M.P. 115-116? C, analysis of which was consistent with the structure for.tris[2 (4 chlorophenylthio)ethyl]isocyanurate.

151,6.557 Found: N, 6.32%.

Example -Tris [2- phenylthio ethyl] iiocyanurate Following substituting phenylthio chloroformate for the 4-chlorophenylthio chloroformate therein'gave phenyl azir idinyl thioformate, M.P. 32-36C., of which 84.3 gm. was then dissolved in 150 ml. of undrie'd p-xylene. Theresulting solution was refiuxe'd for 4.25 hours and allowed to stand for 7 days at room temperature. A-white precipitate of N,N-bis[2-(phenylthio)ethyl] urea M.P. .l45-146.5 C., was formed. The precipitate was filtered and the filtrate a solution of 10.10 g.

N MR and infrared 1 for 7 days, the liquid essentially the procedure of Example 4 but diluted with diethyl ether to giye' 6.8 gm. of white, glittering, flakes having NMR and infrared analyses consistent withthe structure of trisE2-(phenylthioethyl)lisocyanu- Antilysis.-Calculated for .C27H37N3O3S3: S, 17.8%.

Found: S, 17.1%. v

- Example 6 Substituting other aziridinyl formate-s and thioformates of the formula:

Example 7.--Tris [2 (2,4 di chlorophenoxy ethyll' isocyanurate q A reaction vessel equipped with means for stirring, temperature control and refluxing was charged with 50.8 gm. of ethyleneimine (1.82 moles), ll 9.6 gm. of triethylamine (1.82 moles) and 400 ml. of benzene. To this mixture Was "addedasolutien "or 275 gm. (1.21 moles) of 2,4-diclilor'ophenyl chloroformate in 1800 ml. of benzene. Addition was dropwise over a period of about 40 minutes while maintaining a temperature ofabout 20 C. The resulting mixture was digestedfor 3. hours and 20 minutes at room temperature. The reaction product was then filtered to remove I triethylamine hydrochloride and the resulting product evaporatedto.dryness. Residue was 279.7 gm. of a light yellow solid which was washed in benzene, stirred overnight inbenzene', filtered, washed again inbenzene and evaporated under reduced pressure. The resulting solid was dissolved in methanol, Which, on evaporation,

-=. gave 69.7 gm. of a slightly yellow solid, M.P. 90-130 C.

This product: was recrystallized from methanol to give 42,gm. of a White powder having an IR spectrum consistent' with 80% tris[2-(2,4-dichlorophenoxy)ethyllisocyanurate'.Recrystallization of this material from carbon tetrachloride gave a solid, M.P. 151-152 C. The filtrate from this recrystallization was evaporated under reduced pressure to give 128.0 gmr ofamber liquid having an IR spectrum consistent with tris[2- (2,4-dichloro 'phenoxy)ethyl]isocyanurate. The combined yield was 45.4% of theoretical.

Example 8 Substituting other phenyl haloformates and phenyl halothioformates of the formula: Anqlysis. Calculated for C H Cl N O S Calculated YnO wherein Y is chloro, nitro, bromo, or trifiuoromethyl, n is 0-5, and A is oxygen or sulfur, for the dichlorophenyl chloroformate of Example 7 is productive of the corresponding isocyanurates (H), such as the unsubstituted or 2-chloro-, 3-chlor0-, 2,4,6-trichloro-, 2-nitro-, 2,4-dinitro-, 3-nitro, 3,5-dinitro-, 3-trifluoromethyl, 2-chloro-4-nitroand 2,4-dibromo-substituted phenoxyethyl or phenylthioethyl isocyanurates.

It is to be understood that the substitutions of Examples 6 and -8 necessitate no change in reaction conditions other than those obvious to one skilled in the art as dictated by the physical properties of the individual reactants.

Replacing the triethylamine catalyst in Examples 2, 3 and 7 with other tertiary amines such as pyridine, diethylaniline, triethylamine, tributylamine, triethanolamine, triethylen'ediamine, and the like, imposes no new requirements on the reaction, the:e catalysts being used interchangeably with any combination of primary reactants.

We claim:

1. A tri-substituted isocyanurate of the formula:

wherein each Y independently is an electronegative substituent selected from the group consisting of bromo, chloro, nitro,'trihalomethyl and hydrogen, n is an integer of 0-5, and A is oxygen or sulfur.

3,409,618 5 6 2. The compound of claim 1 wherein A is oxygen. References Cited 3. The compound of claim 2 wherein each phenyl UNITED STATES PATENTS 2,4-d' hl b t't td. gmup on) S u 6 2,536,849 1/1951 Kaiser et a1. 260248 4. The com ound of claim 2 wherein each henl groupis4 nitroljsubsmuted p y 5 3,075,979 1/1963 Tazuma m1 260248 5. The compound of claim 1 wherein Y is hydrogen, OTHER REFERENCES bromo, chloro, or nitro.

The compound of Claim 1 wherein n is Iwakura et al.: J. Org. Chem, vol. 25, pp. 1118-23 7. The compound of claim 1 wherein A is sulfur. (1960) QD 8. The compound of claim 7 wherein each phenyl group is 4 chloro substituted 10 HENRY R. JILES, Puma/y Examine].

9. The compound of claim 7 wherein each n is zero. I. M. FORD, Assistant Examiner. 

